Abstract:

A brush holder assembly for a dynamo-electric machine includes a brush
fixture snap-fittingly secured to a shielding fixture. A brush member is
moveably mounted within the brush fixture and includes a recessed region,
and a shunt member. The shunt member includes a first end operatively
connected to the brush member at the recessed region that extends through
an intermediate region to a second end. A constant force spring is
operatively connected between the second end section of the brush and the
brush fixture. The brush holder assembly also includes a shunt retainer
mounted in the brush fixture abutting the brush member. The shunt
retainer includes a first leg portion, a second leg portion and a base
portion. The shunt retainer is configured to maintain proper alignment of
the constant force spring and prevent entanglement of the shunt member.

Claims:

1. A brush holder assembly for a dynamo-electric machine comprising:a
brush fixture including a main body portion having a first end portion
that extends to a second end portion through an intermediate portion
defining a brush chamber, the second end portion including at least one
snap element;a shielding fixture detachably mounted to the brush fixture,
the shielding fixture including a main body having a first end that
extends to a second end through an intermediate wall portion, the
intermediate wall portion including a brush fixture mounting section
provided with at least one snap member, the at least one snap member
being configured to interact with the at least one snap element to
snap-fittingly secure the brush fixture to the shielding fixture;a brush
member moveably mounted within the brush chamber, the brush member
including a main body member having a first end section that extends to a
second end section, the second end section including a recessed region
and a shunt member, the shunt member including a first end operatively
connected to the brush member at the recessed region that extends through
an intermediate region to a second end;a constant force spring
operatively connected between the second end section of the brush and the
brush fixture, the constant force spring applying a constant force urging
the brush member toward the shielding fixture; anda shunt retainer
mounted in the brush chamber and abutting the second end section of the
brush member, the shunt retainer including a first leg portion, a second
leg portion and a base portion, the shunt retainer being configured to
maintain proper alignment of the constant force spring and prevent
entanglement of the shunt member.

2. A brush holder assembly for a dynamo-electric machine comprising:a
brush fixture including a main body portion having a first end portion
that extends to a second end portion through an intermediate portion
defining a brush chamber, the second end portion including at least one
snap element; anda shielding fixture detachably mounted to the brush
fixture, the shielding fixture including a main body having a first end
that extends to a second end through an intermediate wall portion, the
intermediate wall portion including a brush fixture mounting section
provided with at least one snap member, the at least one snap member
being configured to interact with the at least one snap element to
snap-fittingly secure the brush fixture to the shielding fixture.

3. The brush holder assembly according to claim 2, wherein the shielding
fixture includes a mounting frame, the at least one snap member being
formed in the mounting frame.

4. The brush holder assembly according to claim 3, wherein the at least
one snap element comprises a first snap element and a second snap element
arranged on the second end portion of the brush fixture.

5. The brush holder assembly according to claim 4, wherein the at least
one snap member comprises a first snap member and a second snap member,
the first and second snap members being formed on the mounting frame.

6. The brush holder assembly according to claim 1, further comprising: a
cap member snap-fittingly connected to the first end portion of the brush
fixture.

7. A brush holder assembly for a dynamo-electric machine comprising:a
brush fixture including a main body portion having a first end portion
that extends to a second end portion through an intermediate portion
defining a brush chamber;a shielding fixture detachably mounted to the
brush fixture, the shielding fixture including a main body having a first
end that extends to a second end through an intermediate wall portion;a
brush member moveably mounted within the brush chamber, the brush member
including a main body member having a first end section that extends to a
second end section, the second end section including a shunt member;a
spring operatively connected between the second end section of the brush
and the brush fixture, the spring applying a force urging the brush
member toward the shielding fixture; anda shunt retainer mounted in the
brush chamber and abutting the second end section of the brush member,
the shunt retainer including a first leg portion, a second leg portion
and a base portion, the shunt retainer being configured to maintain
proper alignment of the constant force spring and prevent entanglement of
the shunt member.

8. The brush assembly according to claim 7, wherein the shunt retainer is
substantially u-shaped in cross-section with the first leg portion being
joined to the second leg portion through the base portion forming an
interior region.

9. The brush assembly according to claim 8, wherein the spring includes a
coil portion and a leg portion, the leg portion being adapted to engage
with the second end portion of the brush fixture and the coil portion
being adapted engage the second end section of the brush member and nest
within the interior region of the shunt retainer.

10. The brush assembly according to claim 8, wherein the shunt retainer
includes a first locating element arranged on the first leg portion and a
second locating element arranged on the second leg portion, the first and
second locating elements being positioned within the interior region and
configured to restrain movement of the spring.

11. The brush assembly according to claim 7, wherein the base portion of
the shunt retainer includes a recessed portion, the shunt member passing
across the base portion in the recessed portion.

12. The brush assembly according to claim 7, wherein the base portion of
the shunt retainer includes an alignment member, the alignment member
being adapted to substantially prevent axial rotation of the shunt
retainer relative to the brush shield while simultaneously enabling the
shunt retainer to travel longitudinally between the first and second end
portions within the brush chamber.

13. The brush assembly according to claim 7, further comprising: a cap
member snap-fittingly connected to the first end portion of the brush
fixture

14. A brush holder assembly for a dynamo-electric machine comprising:a
brush fixture including a main body portion having a first end portion
that extends to a second end portion through an intermediate portion
defining a brush chamber;a shielding fixture detachably mounted to the
brush fixture, the shielding fixture including a main body having a first
end that extends to a second end through an intermediate wall portion;
anda brush member moveably mounted within the brush chamber, the brush
member including a main body member having a first end section that
extends to a second end section, the second end section including a
recessed region and a shunt member, the shunt member including a first
end operatively connected to the brush member at the recessed region that
extends through an intermediate region to a second end.

15. The brush holder assembly according to claim 14, wherein the recessed
region includes a first and second opposing edge portions joined by a
base portion to define a substantially u-shaped notch in the second end
portion of the brush member.

16. The brush holder assembly according to claim 14, wherein the first end
of the shunt member is operatively connected to the brush member at the
base portion.

17. The brush holder assembly according to claim 14, further comprising: a
spring including a leg portion connected to the second end portion of the
brush shield and a coil portion, the coil portion of the spring directly
abutting the second end section of the brush member without engaging the
shunt member.

18. The brush holder assembly according to claim 17, wherein the brush
shield includes a shunt member guide extending, at least in part between
the first end portion and second end portion within the brush chamber.

19. The brush holder assembly according to claim 18, further comprising: a
terminal element arranged at the first end portion of the brush shield,
the shunt member passing along the shunt member guide to the terminal
element without touching the spring.

20. The brush holder assembly according to claim 18, further comprising: a
cap member snap-fittingly coupled to the first end portion of the brush
shield, the cap member being adapted to retain the terminal element
relative to the brush shield.

Description:

[0002]Dynamo-electric machines, such as generators, motors, and automotive
alternators, may include brushes that facilitate contact between a
spinning rotor and an electrical circuit. More specifically, electrons
pass from the spinning rotor through the brushes and flow into an
electrical circuit that is employed, for example, to provide power to an
automobile or the like. In order to provide protection from a harsh
operating environment, the brushes and other associated elements, are
housed in a brush holder assembly. In addition to shielding the brushes
from harsh operating conditions, the brush holder assembly enhances
operational life for the associated dynamo-electric machine. That is,
friction resulting from contact with the spinning rotor causes the
brushes to wear. If not properly fixtured, the wear would be uneven,
resulting in a loss of contact between the brush(es) and the rotor. Any
such loss of contact would result in machine failure.

BRIEF DESCRIPTION

[0003]According to one aspect of the exemplary embodiment, a brush holder
assembly for a dynamo-electric machine includes a brush fixture having a
main body portion provided with a first end portion that extends to a
second end portion through an intermediate portion defining a brush
chamber. The second end portion includes at least one snap element. The
brush holder assembly also includes a shielding fixture detachably
mounted to the brush fixture. The shielding fixture includes a main body
having a first end that extends to a second end through an intermediate
wall portion. The intermediate wall portion includes a brush fixture
mounting section provided with at least one snap member. The at least one
snap member is configured to interact with the at least one snap element
to snap-fittingly secure the brush fixture to the shielding fixture. A
brush member is moveably mounted within the brush chamber. The brush
member includes a main body member having a first end section that
extends to a second end section. The second end section includes a
recessed region, and a shunt member. The shunt member includes a first
end operatively connected to the brush member at the recessed region that
extends through an intermediate region to a second end. A constant force
spring is operatively connected between the second end section of the
brush and the brush fixture. The constant force spring applies a constant
force that urges the brush member toward the shielding fixture. In
addition, the brush holder assembly includes a shunt retainer mounted in
the brush chamber abutting the second end section of the brush member.
The shunt retainer includes a first leg portion, a second leg portion and
a base portion. The shunt retainer is configured to maintain proper
alignment of the constant force spring and prevent entanglement of the
shunt member.

[0004]According to another aspect of the exemplary embodiment, a brush
holder assembly for a dynamo-electric machine includes a brush fixture
having a main body portion provided with a first end portion that extends
to a second end portion through an intermediate portion that defines a
brush chamber. The second end portion includes at least one snap element.
The brush holder assembly also includes a shielding fixture detachably
mounted to the brush fixture. The shielding fixture includes a main body
having a first end that extends to a second end through an intermediate
wall portion. The intermediate wall portion includes a brush fixture
mounting section that is provided with at least one snap member. The at
least one snap member is configured to interact with the at least one
snap element to snap-fittingly secure the brush fixture to the shielding
fixture.

[0005]According to yet another aspect of the exemplary embodiment, a brush
holder assembly for a dynamo-electric machine includes a brush fixture
having a main body portion provided with a first end portion that extends
to a second end portion through an intermediate portion to define a brush
chamber. A shielding fixture is detachably mounted to the brush fixture.
The shielding fixture includes a main body having a first end that
extends to a second end through an intermediate wall portion. A brush
member is moveably mounted within the brush chamber. The brush member
includes a main body member having a first end section that extends to a
second end section. The second end section includes a shunt member. A
spring is operatively connected between the second end section of the
brush and the brush fixture. The spring applies a force urging the brush
member toward the shielding fixture. In addition, the brush holder
assembly includes a shunt retainer mounted in the brush chamber abutting
the second end section of the brush member. The shunt retainer includes a
first leg portion, a second leg portion and a base portion. The shunt
retainer is configured to maintain proper alignment of the constant force
spring and prevent entanglement of the shunt member.

[0006]According to still another aspect of the exemplary embodiment, a
brush holder assembly for a dynamo-electric machine includes a brush
fixture having a main body portion provided with a first end portion that
extends to a second end portion through an intermediate portion to define
a brush chamber. A shielding fixture is detachably mounted to the brush
fixture. The shielding fixture includes a main body having a first end
that extends to a second end through an intermediate wall portion. The
brush holder assembly also includes a brush member moveably mounted
within the brush chamber. The brush member includes a main body member
having a first end section that extends to a second end section. The
second end section includes a recessed region and a shunt member. The
shunt member includes a first end operatively connected to the brush
member at the recessed region that extends through an intermediate region
to a second end.

[0007]These and other advantages and features will become more apparent
from the following description taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWING

[0008]The subject matter, which is regarded as the exemplary embodiment,
is particularly pointed out and distinctly claimed in the claims at the
conclusion of the specification. The foregoing and other features, and
advantages of the exemplary embodiments are apparent from the following
detailed description taken in conjunction with the accompanying drawings
in which:

[0009]FIG. 1 is a perspective view of a brush assembly constructed in
accordance with exemplary embodiments;

[0010]FIG. 2 is an exploded view of the brush assembly of FIG. 1;

[0011]FIG. 3 is a cross-sectional, side view of the brush assembly of FIG.
1;

[0012]FIG. 4 is a cross-sectional, top plan view of a brush fixture
portion connecting with a shield fixture portion of the brush assembly of
FIG. 1;

[0013]FIG. 5 is a perspective view of a brush member element of the brush
assembly in accordance with exemplary embodiments; and

[0014]FIG. 6 is a partial cross-section view of the brush fixture portion
of the brush assembly of FIG. 1 illustrating a shunt retainer element in
accordance with exemplary embodiments.

[0015]The detailed description explains exemplary embodiments, together
with advantages and features, by way of example with reference to the
drawings.

DETAILED DESCRIPTION

[0016]With initial reference to FIGS. 1-4, a brush holder assembly,
constructed in accordance with exemplary embodiments, is indicated
generally at 2. As will be detailed more fully below, brush holder
assembly 2 includes a shielding fixture 4 that is snap-fittingly
connected to a brush fixture 6. A cap member 8 is also snap-fittingly
connected to brush fixture 6. In accordance with the exemplary embodiment
shown, shielding fixture 4 includes a main body 10 having a first end 14
that extends to a second end 15 through an intermediate or annual wall 16
that collectively define a hollow interior 18. More specifically, first
end 14 defines a base section 22 that is configured to connect with, for
example, an automotive alternator. In addition, shielding fixture 4 is
shown to include a brush fixture mounting frame 26 formed on annular wall
16. Brush fixture mounting frame 26 includes a spacer or wall member 30
as well a first and second snap members 34 and 35 that provide an
attachment point for brush fixture 6.

[0017]In further accordance with the exemplary embodiment shown, brush
fixture 6 includes a main body portion 44 having a first end portion 48
that extends to a second end portion 49 through an intermediate portion
50. First end portion 48 includes a pair of snap elements 52 and 53 that
are configured to snap-fittingly engage with snap members 34 and 35
respectively. With this arrangement, brush fixture 6 is readily secured
to shielding fixture 4 without the need of, for example, sonic welding,
mechanical fasteners, adhesives, and the like. Brush fixture 6 is also
shown to include a first brush chamber 58 and a second brush chamber 59
each of which extend between first and second end portions 48 and 49.
Each brush chamber 58 and 59 includes a corresponding shunt member guide
61 and 62 respectively.

[0018]Brush fixture 6 is further shown to include a first mounting rib 66
positioned adjacent first end portion 48 and a second mounting rib 67
that is positioned adjacent second end portion 49. First mounting rib 66
extends circumferentially about first end portion 48 of brush fixture 6
and is configured to abut brush fixture mounting frame 26 in order to
ensure a robust attachment. Similarly, second mounting rib 67 extends
circumferentially about second end portion 49 and is configured to
receive cap member 8. More specifically, cap member 8 includes a
plurality of clip members 72 through 74 that are configured to
snap-fittingly engage with second mounting rib 67. Brush fixture 6 is
also shown to include a flange 77 which, as will be discussed more fully
below, provides a mounting surface for electric connections associated
with brush holder assembly 2. More specifically, brush holder assembly 2
includes first and second brush assemblies 84 and 85 that are configured
to transmit electrical energy from a rotating shaft 90 (see FIG. 3) to a
stationary electronic coupling. However, as each brush assembly 84 and 85
is similarly constructed, a detailed description will follow with respect
to brush assembly 84 with an understanding that brush assembly 85
includes similar components.

[0019]As best shown in FIGS. 2 and 3, brush assembly 84 includes a
constant force spring 95 having a leg or clip portion 97 that is
configured to matingly engage with first end portion 48 of brush fixture
6. Clip portion 97 extends to a coil or brush contact portion 99.
Constant force spring 95 is configured to extend and contract within
first brush chamber 58. More specifically, brush contact portion 99 is
configured to engage and exert a force onto a brush member 105. In this
manner, constant force spring 95 ensures that brush member 105 remains in
contact with the rotary component (not shown) of the associated electric
machine.

[0020]As best shown in FIG. 5, brush member 105 includes a main body
member 110 having a first end section 112 that extends to a second end
section 113. Brush member 105 is also shown to include a recessed region
117 formed in second end section 113. Recessed region 117 includes a
first edge portion 120, a second, opposing, edge portion 121 and a base
portion 122 that collectively define a U-shaped notch 123. A shunt member
127 is electrically connected to brush member 105 at recessed region 117
and positioned, at least in part, in shunt member guide 61. More
specifically, shunt member 127 includes a first end 129 that extends from
base portion 122 to a second end 130 through an intermediate section 131.
As will be described more fully below, intermediate section 131 includes
a U-shaped bend portion 132 that resides within shunt member guide to
ensure that shunt member 127 does not contact constant force spring 95.
In addition to U-shaped bend 132 formed in shunt member 127, brush
assembly 84 includes a shunt retainer 136 positioned at second end
section 113 of brush member 105. As will be discussed more fully below,
shunt retainer 136 provides additional structure that ensures shunt
member 127 does not contact constant force spring 95.

[0021]As best shown in FIG. 6, shunt retainer 136 includes a first leg
portion 146 that extends to a second leg portion 147 through a base
portion 148 that collectively define an interior region 150. In
accordance with the exemplary embodiment shown, shunt retainer 136
further includes a first locating element 164 arranged on an inner
surface (not separately labeled) of first leg portion 146 and a second
locating element 165 arranged on an inner surface (not separately
labeled) of second leg portion 147. Each locating element 164 and 165
projects from respective ones of first and second leg portions 146, 147
into interior region 150. With this arrangement, first and second
locating elements 164 and 165 are configured to retain brush contact
portion 99 of constant force spring 95. That is, as brush contact portion
99 moves along first brush chamber 58, first and second locating elements
164 and 165 ensure that shunt retainer 136 moves in conjunction with
brush member 105. In this manner, shunt retainer 136 ensures that shunt
member 127 remains within shunt member guide 61 and out of the way of
constant force spring 95. In addition to the first and second locating
elements 164 and 165, shunt retainer 136 includes a recessed portion 169
formed on a first side (not separately labeled) of the base portion 148
and an alignment member 174 formed on an opposing side (not separately
labeled) of base portion 158. Recessed portion 169 accommodates
intermediate section 131 of shunt member 127 while alignment member 174
ensures that shunt retainer 136 does not rotate within first brush
chamber 58. Finally, brush assembly 84 is shown to include a terminal
member 180 that is configured to electrically interconnect with second
end 130 of shunt member 127. Terminal member 180 is mounted to flange 77
and transfers electrical current from brush member 105 through shunt
member 127 to particular electrical loads within, for example, an
automobile.

[0022]At this point, it should be understood that the exemplary embodiment
provide a simple structure for housing a brush assembly associated with a
dynamo-machine. That is, by providing a snap-fitting engagement between
brush fixture 6 and shield fixture 4, construction and manufacture of
brush holder assembly 2 is simplified. In addition, by providing notches
within brush member 105, as well as the inclusion of shunt retainers 136,
additional components are not required to ensure that contact between
shunt member 127 and constant force spring 95 is eliminated. Finally,
while shown and described in connection with an automotive alternator, it
should be readily apparent to one of ordinary skill in the art that the
brush holder assembly in accordance with the exemplary embodiment could
be employed in a wide variety of dynamo-electric machines.

[0023]While the exemplary embodiments have been described in detail in
connection with only a limited number of embodiments, it should be
readily understood that the exemplary embodiments are not limited to such
disclosed embodiments. Rather, the exemplary embodiments can be modified
to incorporate any number of variations, alterations, substitutions or
equivalent arrangements not heretofore described, but which are
commensurate with the spirit and scope of the exemplary embodiments.
Additionally, while various embodiments of the exemplary embodiments have
been described, it is to be understood that aspects of the exemplary
embodiments may include only some of the described embodiments.
Accordingly, the exemplary embodiment is not to be seen as limited by the
foregoing description, but is only limited by the scope of the appended
claims.